1. Field of the Invention
The present invention relates to a keyboard-video-mouse (KVM) switch, and more particular to a KVM switch having a universal input and programmable universal serial bus (USB) hub.
2. Description of Prior Art
At present, a KVM switch is generally used for achieving the effect of controlling and operating a plurality of computers (or servers) by one set of peripherals as shown in FIG. 1, and an end of the KVM switch 90 is connected to a plurality of computers 91, and another end is connected to a keyboard 92, a video display device 93, and a mouse 94. Although the conventional KVM switch can share the function of the keyboard-video-mouse set by its connection. However, a console of the conventional KVM switch includes a USB input/output device connected to a fixed input/output interface and allows users to connect the keyboard, video display device and mouse to specific ports only, but the use of ports cannot be changed or other USB devices such as flash devices, card readers, and digital cameras cannot be connected freely, and thus the scope of applicability and the convenience of operations are limited. Therefore, many USB devices achieve the function of switching operations by switching the connection of a hub, and such arrangement is not an ideal application, since the console input/output interface is fixed, and a corresponding simulation program and a compatible format are limited. The compatibility issue occurs in various different USB devices. Furthermore, a complicated switching circuit and a control firmware programs are required for switching the connection of the hub, not mentioning the separate switching control of any port to a computer port. Therefore, the structure and application of the USB input/output interface of present existing KVM switches and hubs require further improvements.
In view of the shortcomings of the conventional KVM switch, the inventor of the present invention based on years of experience in the related industry to conduct extensive researches and experiments, and finally developed a KVM switch having a universal input and programmable USB hub in accordance with the present invention, and the KVM switch can be adjusted dynamically to provide convenience and economic benefits.